Gas mask



Aug. 18, 1936. E. w. BULLARD GAS MASK Filed July 23, 1934 Patented Aug.18, 1936 UNITED STATES PATENT OFFICE Edward W. Bullard,

San Francisco, Calif.. as-

signor, by mesne assignments, to E. D. Bullard Company, oi' CaliforniaSan Francisco, Calif., a corporation Application July 23, 1934, SerialNo. 736,521

9 Claims.

My invention relates to gas masks, and more particularly to improvementsin the face piece and exhalation valve mounting of such masks.

It is among the objects of my invention to simplify the construction andreduce the weight and bulkiness of gas masks.

Another object of my invention is to provide a gas mask construction inwhich the exhalation valve seat is formed as an integral part of theface piece.

Another object of my invention is to provide means for reenforclng theportions of the face piece which comprise the valve seat.

Still another object of my invention is to provide an improved mountingfor the valve guard.

The invention possesses other objects and features of advantage, some ofwhich, with the foregoing, will be set forth in the followingdescription of my invention. It is to be understood that I do not limitmyself to this disclosure of species of. my invention, as I may adoptvariant embodiments thereof within the scope of the claims.

Referring to the drawing:

Figure 1 is a vertical sectional view of my improved mask, showing theportions of the face piece embodying the valve; and

Figure 2 is a detailed sectional view showing a modified form ofstructure.

In terms of broad inclusion, the gas mask embodying my inventioncomprises a face piece, and an exhalation valve for the mask andcomprising a valve seat formed as an integral part of the face piece. Areinforcing ring is preferably provided in the face piece about thevalve seat, and means are preferably provided on the face piece forholding the valve guard.

In greater detail, and referring particularly to Figure 1, the gas maskof my invention comprises a face piece 2, preferably of rubber, moldedto t over the face of the wearer. A molded rubber face piece of the typedisclosed in my copending application, Serial No. 584,353, filed January2, 1932, is preferably employed.

In my present improved structure the portions 3 of the face piece infront of the wearers mouth are thickened to provide the base portions ofthe exhalation valve. In other words, the base portions of the valve aremolded as an integral part of the rubber face piece. 'I'his eliminatesthe usual metal nozzle at this point, and provides a mask which islighter, more compact and not subject to the development of leaw joints.

The portion 3 is of generally circular or disklike formation and isprovided with` a plurality (Cl. 12S-140) of breathing apertures 4. Theseapertures are closed against the entrance of air by a circular diaphragm6, also preferably of rubber. The diaphragm is held against the valvebase or seat 3 by a plug portion i extending through the base. Thedetails of this type of valve structure are disclosed in my copendingapplication, Serial No. 718,652, filed April 2, 1934.

Means are provided for reenforcing the por tions of the face piece aboutthe valve seat. This 1c may be accomplished by embedding a metallic ring8 in the portions 3 when the face piece is molded. Another way, as shownin Figure 2, is to form a T-shaped recess 9 in the face piece, and thensubsequently inserting a reenforcing ring in the recess.

A guard Il, preferably of metal, is provided over the valve structure,and means are provided in the face piece for securing the guard. Asshown in Figure 2, a recess l2 is provided inthe 20 face piece about thevalve seat and a beaded tongue I3 is provided about the outer edge ofthe recess. Referring again to Figure 1, the guard Il is provided with aflange i4 adapted to engage the recess I2, and a. retaining ring it,preferably of spring metal, is provided to bear against the tongue tohold the guard securely in position.

By the improved construction, in which the seat of the valve is fo'rmedas an integral part of g@ the face piece, the structure of the mask as awhole is materially simplied, and the added weight and bulkiness of theusual metal nozzle is eliminated. Furthermore, and this is an iinportantpoint in gas mask design,rthe improved structure is characterized by theabsence of possible leaky joints between the valve and the face piece.

I claim:

1. An exhalation valve comprising a base por- 40 tion including a valveseat, and a reenforcing ring, said base portion having an annularT-shaped recess about the seat for receiving the ring, the top portionof the T-shaped recess lying 4 within the body of the base to provide aninternal groove for holding the ring and the leg portion of the T-shapedrecess opening out on the surface of the base to provide an opening foradmitting the ring.

2. An exhalation valve comprising a base portion including a valve seatand having an annular recess aboutl the seat, a guard for the valve andhaving a flange portion engaging said recess, and a retaining ringsurrounding the guard adjacent 55 said recess and bearing against thevalve base portion to hold the guard.

l 3. An exhalation valve comprising a base portion including a valveseat, and having an annular recess about the seat, a guard for the valveand Y having a flange portion engaging said recess, said valve baseportion having a tongue adjacent the recess and lying against the guard,and a retaining ring surrounding the guard and pressing against saidtongue for holding the guard.

4. A gas mask comprising a face piece, an exhalation valve for the maskand comprising a seat formed integrally with the face piece, and areeniorcing ring embedded in the face piece behind the valve seat.

5. A gas mask comprising a face piece of molded rubber, an exhalationvalve for the mask and comprising a seat of rubber molded as an integralpart of the face piece, a reenforcing ring in the face piece about thevalve seat, said face piece having a recess about about the seat and atongue adjacent one side of the recess, a guard for the valve and havinga ange portion engaging said recess, and a retaining ring surroundingthe guard and pressing against said tongue for holding the guard.

6. A gas mask comprising a face piece, an apertured valve seat formedintegrally with the face piece and having a concave outer surface, and aresillently flexible diaphragm over the valve seat and exed intoconformity with said concave surface.

7. A gas mask comprising a face piece of molded rubber, a valve seat ofrubber molded as an integral part of the face piece; said valve seatbeing apertured and having a concave outer surface, and a resilientlyflexible diaphragm over the valve seat and flexed into conformity withsaid concave surface.

8. An exhalation valve comprising an apertured rubber valve seat havinga concave outer surface, a resillently flexible diaphragm over the valveseatand flexed into conformity with said concave surface, and areinforcing ring in the valve seat for holding the latter in shape.

9. A gas mask comprising a face piece of molded rubber, a valve seat ofrubber molded as 20 an integral part of the face piece, said valve seatbeing apertured and having a concave outer surface, and a resillentlyflexible diaphragm over the valve seat and flexed into conformity withthe valve seat for holding the latter in shape. EDWARD W. BULLARD.

Vsaid concave surface, and a reinforcing ring in 25

